Providing soap mounted on a razor handle or cartridge is known. For example, U.S. Pat. No. 6,584,690 describes a razor that carries a shaving preparation, e.g., in the form of a solid cake of soap that surrounds the cartridge. Further 2-in-1 razors are not new and have also been marketed under the Venus Breeze® line of razors and the Schick® Intuition® line of razors. See also US Patent Publ Nos. 2006/225285A and 2006/080837A, and U.S. Pat. No. 7,811,553.
Addition of pyrithione sources, such as zinc pyrithione, into soap bars for antibacterial purposes has been described. See e.g. US 2008/0249136 A1. The zinc pyrithione (“ZPT”) can be added in the form of small or fine particles. Antibacterial bar soap including ZPT are often used because the surfactancy of the soap is believed to help in removal of microbial entities or microbials on the skin, while the antimicrobial agent such as the ZPT can deposit onto skin to provide residual protection against subsequent invasion.
One problem with the introduction of pyrithione source into soap bars is that during manufacturing, handling or storage of a bar soap, various metallic parts of the manufacturing equipment, for example pipes, nozzles may be contacted with the bar soap. In some situation, such contact can maintain a long time (e.g. overnight to 24 hours), and at a relatively elevated temperature. Such contact has the potential of causing a color change of the bar soap, so called “discoloration”, which is from a colored precipitate. A number of solutions toward this pyrithione discoloration problem have been described. For example, in U.S. Pat. No. 4,161,526, JP Patent Publication 2001-278863A, U.S. Pat. Nos. 4,482,715, 4,957,658 and 4,818,436.
Although the addition of pyrithione sources into bar soaps is believed to provide antibacterial benefits in a washing context, the use of bar soaps in a shaving context has encountered other complexities. In particular, when skin is shaved with a razor cartridge, the razor blades can remove most if not all items present on the skin, such as, removing hairs, surface skin cells, shaving preparations, soap residue, skin care actives and any other ingredients or actives present on the skin before contacting the blades. As such, there remains a need to deliver antibacterial benefits such as those from antibacterial soaps in a shaving context, and preferably while avoiding discoloration issues.